The goal of the Animal Management and Transgenic Mouse Core is to provide transgenic and the indicated knockout animals bred into distinct genetic backgrounds to each of the three projects of this Program Project. Due to the extensive numbers of mice that are required for each project, and since some of the genotypes are shared across more than one project, in order to ensure optimal quality control, mouse identification and smooth flow of animals, the functions of breeding and genotyping of animals are best done within a core by a team dedicated to that function. Further, the ordering, receipt, entry into the database, and distribution of aged and young Fischer 344 from the NIA colonies will be managed by Core C. In Core C, this team will be led by Dr. Shi Fang Van, and co-lead by Dr. Thomas Martin of the Institute of Comparative Medicine. Dr. Van has extensive experience in the breeding and genotyping of transgenic mice. Mechanisms are in place in Core C to facilitate mouse breeding, weaning, tattooing, tail biopsy and Southern blotting/PCR to determine genotype. Multiple quality controls are in place to ensure consistency of the strains by Southern, Northern, Western blotting of representative mice per strain at specified intervals, along with activity assays as indicated. Dr. Martin has extensive experience in the care and use of mice and has designed a thorough description of the care and management of aged mouse in our colonies. Core C will serve each of the three projects during each of the five years of the Program Project.